The invention relates to equipment for painting lines on an outdoor surface and, in particular, to such equipment which may have as its chief function the painting of demarkation lines in parking lots and the like.
The painting of lines to indicate parking spaces in parking lots and the like is generally a labor-intensive job requiring the cooperative labor of four or five men since it must often be accomplished in a relatively short period of time. Such lines may be painted by hand or a manually manipulated cart may be utilized. Large equipment such as used for painting the center lines on a highway is generally too awkward for tasks other than that for which it has been specially designed. Thus, a need exists and has existed for some time for a relatively compact self-propelled mobile unit which can paint lines in a parking lot or the like accurately and rapidly.
In considering the prior art, attention is invited in particular to a patent of Sweet, U.S. Pat. No. 3,373,938 of Mar. 19, 1968, which discloses a line-marking vehicle having a boom mounted spray paint nozzle capable of painting lines on both horizontal and vertical surfaces. In such device, the painting assembly is carried by a relatively small hand truck and the boom supporting the spray nozzle is mounted on the truck for both vertical and lateral adjustment relative thereto. Rotation of handles produces vertical and lateral adjustments about a pivotal sleeve. A patent to Harding et al, U.S. Pat. No. 3,477,352 of Nov. 11, 1969, discloses the use of a wheel to support the forward end of a boom upon which is mounted a spray gun. The rear end of the boom is pivotally connected to a vehicle chassis so that the boom can be swung up to its storage position. A further highly portable road marking device in the prior art is illustrated in the patent to Glasgow, U.S. Pat. No. 1,999,563 of Apr. 30, 1935. This patent teaches a spray gun mounting bracket wherein the gun can be readily released from its mounting for cleaning and other use. Other devices of general interest are disclosed in the patents to Schroth, U.S. Pat. No. 2,074,623 of Mar. 23, 1937, to Hollingshead, U.S. Pat. No. 2,076,370 of Apr. 6, 1937, to Gardner, U.S. Pat. No. 2,812,211 of Nov. 5, 1957, and to Wilson, U.S. Pat. No. 3,046,854 of July 31, 1962.